Device and Method for Handling Channel Access Procedure

ABSTRACT

A device for handling channel access procedure includes a storage device and a processing circuit coupled to the storage device and configured to execute instructions stored in the storage device. The storage device is configured for storing the instructions of receiving an indication for an uplink transmission; determining at least one parameter of the device for a listen-before-talk procedure according to a capability of the device or a signaling from a base station; and performing the uplink transmission according to the indication.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/757,173 filed on Nov. 8, 2018, which are incorporated herein byreference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a device and method used in a wirelesscommunication system, and more particularly, to a device and method forhandling channel access in an unlicensed band.

2. Description of the Prior Art

With the advance of wireless communication technology, long-termevolution (LTE) could be of crucial importance because of its peak datarate and throughput by using advanced techniques, such as carrieraggregation (CA), dual connectivity, licensed-assisted access (LAA), andso on.

In the LAA, abase station transmits an uplink (UL) grant during achannel occupancy time on an unlicensed carrier, to the UE. The UEperforms a listen-before-talk (LBT) procedure (also referred to as achannel access procedure or clear channel assessment) before performingthe UL transmission in the channel occupancy time on the unlicensedcarrier.

On the other hand, the beam may have beam direction and beamwidthattributes. Compared to the UE having restricted beamwidth due tohardware restriction, abase station may have more flexibility onadjusting its beamwidth in order to provide various services. This maylead to fairness problems. Additionally, when different UL transmissionsrequiring different beam directions are overlapped or spaced apart by alimited time interval, the UE able to focus its beam in only one beamdirection at a time may find out the infeasibility to perform the LBTprocedure. In the prior art, it is not clear how to handle the LBTprocedure in a complex beam direction or beamwidth condition.

SUMMARY OF THE INVENTION

The present invention therefore provides a device and method forhandling channel access in an unlicensed band to solve theabovementioned problems.

A device for handling channel access procedure includes a storage deviceand a processing circuit coupled to the storage device and configured toexecute instructions stored in the storage device. The storage device isconfigured for storing the instructions of receiving an indication foran uplink transmission; and determining at least one parameter of thedevice for a listen-before-talk procedure according to a capability ofthe device or a signaling from a base station; and performing the uplinktransmission according to the indication.

A device for handling channel access procedure includes a storage deviceand a processing circuit coupled to the storage device and configured toexecute instructions stored in the storage device. The storage device isconfigured for storing the instructions of determining a first spatialdomain filter for a first uplink transmission; and determining a secondspatial domain filter for a second uplink transmission.

A method for handling channel access procedure includes receiving anindication for an uplink transmission; and determining at least oneparameter of the device for a listen-before-talk procedure according toa capability of the device or a signaling from a base station; andperforming the uplink transmission according to the indication.

A method for handling channel access procedure includes determining afirst spatial domain filter for a first uplink transmission; anddetermining a second spatial domain filter for a second uplinktransmission.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a wireless communication systemaccording to an example of the present invention.

FIG. 2 is a schematic diagram of a device according to an example of thepresent invention.

FIG. 3 is a flowchart of a method according to an example of the presentinvention.

FIG. 4 to FIG. 8 are schematic diagrams associated with the method shownin FIG. 3.

FIG. 9 is a flowchart of a method according to an example of the presentinvention.

FIG. 10 to FIG. 12 are schematic diagrams associated with the methodshown in FIG. 9.

FIG. 13 is a flowchart of a method according to an example of thepresent invention.

FIG. 14 to FIG. 17 are schematic diagrams associated with the methodshown in FIG. 13.

FIG. 18 is a flowchart of a method according to an example of thepresent invention.

DETAILED DESCRIPTION

FIG. 1 is a schematic diagram of a wireless communication system 10according to an example of the present invention. The wirelesscommunication system 10 briefly includes a network 100 and a pluralityof communication devices 190. The network 100 and a communication device190 may communicate with each other via one or more carriers of licensedband(s) and/or unlicensed band(s).

In FIG. 1, the network 100 and the communication devices 190 are simplyutilized for illustrating a structure of the wireless communicationsystem 10. The network 100 may include at least one base station BS tocommunicate with a communication device 190. The network 100 may be aradio access network (RAN) including at least one evolved Node-B (eNB)and/or gNB (also referred to as 5G BS or new radio (NR) BS). In general,a base station BS may also be used to refer any of the eNB and the gNB.

A communication device 190 may be a user equipment (UE), a machine typecommunication (MTC) device, a mobile phone, a laptop, a tablet computer,an electronic book, a portable computer system, a vehicle, or anaircraft. In addition, each of the base stations BS and thecommunication devices 190 may be seen as either a transmitter or areceiver according to transmission direction. For an uplink (UL), thecommunication device 190 is the transmitter and the network 100 is thereceiver. For a downlink (DL), the network 100 is the transmitter andthe communication device 190 is the receiver.

FIG. 2 is a schematic diagram of a device 20 according to an example ofthe present invention. The device 20 may be a communication device 190or the base station BS shown in FIG. 1, but is not limited herein. Thedevice 20 may include a processing circuit 200 such as a microprocessoror Application Specific Integrated Circuit (ASIC), a storage device 210and a communication interfacing device 220. The storage device 210 maybe any data storage device that may store a program code 214 to beaccessed and executed by the processing circuit 200. Examples of thestorage device 210 include but are not limited to a subscriber identitymodule (SIM), read-only memory (ROM), flash memory, random-access memory(RAM), hard disk, optical data storage device, non-volatile storagedevice, non-transitory computer-readable medium, etc. The communicationinterfacing device 220 includes at least one transceiver and is used totransmit and receive signals (for instance, data, messages and/orpackets) according to processing results of the processing circuit 200.

FIG. 3 is a flowchart of a method 30 according to an example of thepresent invention. The method 30 may be utilized in a communicationdevice 190, for handling a listen-before-talk (LBT) procedure (alsoreferred to as a channel access procedure) in an unlicensed band. Themethod 30 includes the following steps:

Step 300: Start.

Step 302: Receiving an indication for an uplink transmission.

Step 304: Determining at least one parameter of the communication device190 for an LBT procedure on a first carrier according to the (antenna)capability of the communication device 190 or a signaling from the basestation BS.

Step 306: Performing the uplink transmission according to theindication.

Step 310: End.

In the method 30, the communication device 190 may report its (antenna)capability to the base station BS. In some embodiments, thecommunication device 190 reports its (antenna) capability through asignal (for example, a signal SS shown in FIG. 4) such as a radioresource control (RRC) signal. In some embodiments, the (antenna)capability of the communication device 190 may include beamwidth of thecommunication device 190. Here, beamwidth (also referred to as 3 dBbeamwidth or half power beamwidth) in antenna radiation pattern is theangle between opposite half-power (−3 dB) points of a main lobe withrespect to the peak effective radiated power of the main lobe. In someembodiments, the beamwidth of the communication device 190 may be aroundX degrees (for example, X=30, or X=60) or in a range of Y degrees to Zdegrees (for example, Y=30, Z=60). In some embodiments, the beamwidth ofcommunication device 190 may be wide beamwidth (for example, thebeamwidth may be limited as, for example, around 60 degrees), narrowbeamwidth (for example, the beamwidth may be limited as (or within), forexample, around 30 degrees), or variable beamwidth. The communicationdevice 190 having variable beamwidth may switch its beam shape betweenwide beamwidth and narrow beamwidth. In some embodiments, the (antenna)capability of the communication device 190 may include spatial domainfilter type of the communication device 190. The spatial domain filtertype may be categorized into spatial domain filter type one (whichcorresponds to narrow beamwidth), spatial domain filter type two (whichcorresponds to wide beamwidth), and spatial domain filter type three(which corresponds to variable beamwidth).

Subsequently, the base station BS may perform a (base station side)(directional) LBT (for instance, Cat-4 LBT) procedure (for example, anLBT procedure BSLBT shown in FIG. 4) in an unlicensed band to reserve achannel occupancy time (for example, a channel occupancy time CCT shownin FIG. 4). In Step 302, the communication device 190 may receive anindication for a UL transmission (for example, a UL transmission ULTshown in FIG. 4). In some embodiments, the base station BS may perform aDL transmission (for example, a DL transmission DLT shown in FIG. 4)during the channel occupancy time CCT. In some embodiments, the basestation BS may transmit a UL grant related downlink control information(DCI) (for example, a UL grant related DCI 410 shown in FIG. 4) duringthe channel occupancy time CCT. The UL grant related DCI 410 instructsthe communication device 190 to perform a UL transmission (for example,a UL transmission ULT shown in FIG. 4). The UL grant related DCI 410 maybe transmitted by the base station BS to the communication device 190 inthe unlicensed band. The UL grant related DCI 410 may be transmitted bythe base station BS on a physical DL control channel (PDCCH).

The communication device 190 may share the channel occupancy time CCT.Before the UL transmission ULT in response to the UL grant related DCI410, the communication device 190 may also perform a (communicationdevice side) (directional) LBT procedure (for example, an LBT procedureCDLBT shown in FIG. 4) in the unlicensed band during the channeloccupancy time CCT. By means of the LBT procedure CDLBT, thecommunication device 190 senses and determines whether the unlicensedband is available or not. If available, the communication device 190 maythen perform the UL transmission ULT in the unlicensed band during thechannel occupancy time CCT in Step 306 if the LBT procedure CDLBT forthe UL transmission ULT is successful. The communication device 190 mayperform one shot (or short) LBT procedure CDLBT, which may last forexample for 25 us, according to, for example, a command from the basestation BS. Particularly, the LBT procedure CDLBT performed by thecommunication device 190 is shorter than the LBT procedure BSLBTperformed by the base station BS.

On the other hand, different from the communication device 190 havingrestricted beamwidth due to hardware restriction, the base station BSmay have more flexibility on adjusting its beamwidth in order to providevarious services. When the base station BS performs the LBT procedureBSLBT with narrow beamwidth, it may filter certain nodes (for example,nodes 450 shown in FIG. 4) outside its beam coverage and there would beless interference detected by the base station BS. The nodes 450 may bea communication device 190 or the base station BS shown in FIG. 1, butis not limited herein. If the communication device 190 performs the LBTprocedure CDLBT with wide beamwidth, it may cover more nodes 450 withinits beam coverage than the base station BS does. The communicationdevice 190 should evaluate interference during the LBT procedure CDLBTto be higher than the interference evaluation conducted by the basestation BS during the LBT procedure BSLBT, and therefore aborts thefollowing UL transmission ULT. However, the communication device 190 maydetect little interference as it performs a shorter directional LBTprocedure CDLBT. This may lead to fairness problem among radio accesstechnologies. For example, the nodes 450 which is covered by thecommunication device 190 but exposed by the base station BS mayexperience unfairness because interference detected by the nodes 450increases when the communication device 190 insists to perform the ULtransmission ULT.

To solve the fairness problem, the communication device 190 may adjustits parameter for the LBT procedure CDLBT according to its (antenna)capability in Step 304. In some embodiments, the communication device190 adjusts at least one parameter of the communication device 190 forthe LBT procedure CDLBT according to the (antenna) capability of thecommunication device 190 in Step 304. In some embodiments, thecommunication device 190 determines or adjusts at least one parameter ofthe communication device 190 for the LBT procedure CDLBT according tosignaling from the base station BS in Step 304.

An LBT procedure may involve energy detection to determine if a channelis occupied. In some embodiments, the at least one parameter of thecommunication device 190 may thus include an (energy detection)threshold during the LBT procedure CDLBT. The communication device 190may adjust the (energy detection) threshold according to its capabilityand/or signaling from the base station BS. FIG. 4 is a schematic diagramassociated with the method 30 shown in FIG. 3. In FIG. 4, a dashed thinline with dots denotes approximate extent of the beam coverage of thebase station BS for the LBT procedure BSLBT, and a dashed thick linewith dots denotes approximate extent of the beam coverage of thecommunication device 190 for the LBT procedure CDLBT. It should beclearly understood that the beam coverage may have other shapes and isnot limited to those shown in FIG. 4.

In FIG. 4, the communication device 190 may report its (antenna)capability which belongs to wide beamwidth through a signal SS. In someembodiments, the UL grant related DCI 410 may include a field (forexample, a field THindicator) to indicate the (energy detection)threshold (for example, a threshold THadj) for the communication device190 to perform the LBT procedure CDLBT. In some embodiments, the fieldTHindicator in the UL grant related DCI 410 may be related to the(antenna) capability of the communication device 190. The fieldTHindicator in the UL grant related DCI 410 may be an N bit (forinstance, N=2) information, and may be, for instance, 00, 01, 10, or 11.In some embodiments, the (energy detection) threshold (for example, thethreshold THadj) may be configured by higher layer signals such as RRCand/or medium access control (MAC) signal, and thus may not be indicatedin the UL grant related DCI 410. The communication device 190 mayperform the LBT procedure CDLBT with wide beamwidth according to the(energy detection) threshold of lower energy level before the ULtransmission ULT.

If the (energy detection) threshold during the LBT procedure CDLBT islow, the communication device 190 tends to determine that theinterference is high. It is because the intensity of noises detected bythe communication device 190 is more easily to be higher than the(energy detection) threshold. In other words, the communication device190 of wide beamwidth is more sensitive to certain nodes 450 within thebeam coverage of the communication device 190 when the (energydetection) threshold during the LBT procedure CDLBT is low. Thisprevents the communication device 190 from performing the following ULtransmission ULT, and thus the channel would not be occupied by thecommunication device 190. In this manner, the fairness problem isalleviated.

A channel sensing time may be a length of time that the LBT procedureCDLBT lasts or continues. The channel sensing time may correspond to acontention window (CW) size. The channel sensing time may be acontention window or sensing interval. In some embodiments, the at leastone parameter of the communication device 190 may thus include a channelsensing time for the LBT procedure CDLBT. The communication device 190may adjust the channel sensing time for the LBT procedure CDLBTaccording to its capability and/or signaling from base station BS. FIG.5 is a schematic diagram associated with the method 30 shown in FIG. 3.The transmission sequences before and after adjustment of the channelsensing time in the time domain are illustrated at the top and bottom ofFIG. 6 respectively. In FIG. 5, the communication device 190 may reportits (antenna) capability which belongs to wide beamwidth through asignal SS. In some embodiments, the UL grant related DCI 410 may includeinformation about the channel sensing time for the communication device190 to perform the LBT procedure CDLBT. In some embodiments, the basestation BS may instruct which kinds of long (or short) LBT procedure thecommunication device 190 should perform or how long the LBT procedureCDLBT should be. In some embodiments, the information about the channelsensing time may be configured by higher layer signals such as RRCand/or MAC signal, and thus may not be indicated in the UL grant relatedDCI 410.

In some embodiments, the communication device 190 may perform the LBTprocedure CDLBT with wide beamwidth in the duration of longer channelsensing time before UL transmission ULT. In some embodiments, theinformation about the channel sensing time may exclude one shot LBTprocedure, which is about 25 microseconds in terms of the channelsensing time, when the communication device 190 reports its (antenna)capability is limited to wide beamwidth. When the communication device190 performs the LBT procedure CDLBT with wider beamwidth, thecommunication device 190 listens longer so as to determine thesurrounding interfere more accurately. That is to say, the communicationdevice 190 is more sensitive to certain nodes 450 within the beamcoverage of the communication device 190 when the longer channel sensingtime extends. Besides, the communication device 190 tends to determinethat the interference is high. This prevents the communication device190 from performing the following UL transmission ULT, and thus thechannel would not be occupied by the communication device 190. In thismanner, the fairness problem is alleviated.

On the other hand, the narrower the beamwidth, the fewer the nodes 450covered within the beam coverage of the communication device 190. Inthis case, even short channel sensing time may be enough. In someembodiments, the communication device 190 may perform the LBT procedureCDLBT with narrow beamwidth in the duration of shorter channel sensingtime before UL transmission ULT. In some embodiments, the informationabout the channel sensing time may include one shot LBT procedure, whichis about 25 microseconds in terms of the channel sensing time, when thecommunication device 190 reports its (antenna) capability is narrowbeamwidth. When the communication device 190 is able to provide beams ofnarrow beamwidth, interference may be reduced, and one shot LBTprocedure or short LBT procedure is allowed, meaning that the contentionwindow size may be small. The fairness problem is not severe. In someembodiments, the communication device 190 with wider beamwidth (or withnarrower beamwidth) itself knows that the listening step should lastlonger (shorter). In such a situation, there is no need for the basestation BS to instruct the communication device 190 to listen longer (orshorter). The communication device 190 defaults to spend more (or less)time on listening; moreover, the channel sensing time is long (orshort).

If the beamwidth of the communication device 190 is variable, beamwidthadjustment is a more direct approach to solve the fairness problem. Insome embodiments, the at least one parameter of the communication device190 includes beamwidth for the communication device 190 to perform theLBT procedure CDLBT. In some embodiments, the at least one parameter ofthe communication device 190 may include spatial domain filter type forthe communication device 190 to perform the LBT procedure CDLBT. Thecommunication device 190 may adjust its beamwidth corresponding to aspatial domain filter type according to its capability and/or signalingfrom the base station BS. FIG. 6 is a schematic diagram associated withthe method 30 shown in FIG. 3. The transmission sequences before andafter beamwidth adjustment in the time domain are illustrated at the topand bottom of FIG. 6 respectively.

In FIG. 6, through a signal SS, the communication device 190 may reportits (antenna) capability which belongs to variable beamwidth, meaningthat the communication device 190 may switch between wide beamwidth andnarrow beamwidth and that the spatial domain filter type three isadopted. Information about beamwidth adjustment and/or quasi co-location(QCL) assumption for the LBT procedure CDLBT may be transmitted by meansof the UL grant related DCI 410. When the beamwidth of base station BSperforming LBT procedure BSLBT is narrow, the communication device 190performs the LBT procedure CDLBT with narrow beamwidth before the ULtransmission ULT. Likewise, when the beamwidth of base station BSperforming LBT procedure BSLBT is wide, the communication device 190changes its beamwidth and performs the LBT procedure CDLBT with widebeamwidth before the UL transmission ULT. In this manner, the fairnessproblem is alleviated.

In some embodiments, the communication device 190 employs a narrow beamfor a UL sounding transmission and an LBT procedure CDLBT prior to theUL sounding transmission, the base station BS instructs thecommunication device 190 to perform a UL data transmission and an LBTprocedure CDLBT prior to the UL data transmission with narrow beam. Insome embodiments, the base station BS performs the LBT procedure BSLBTwith narrow beamwidth, and the base station BS instructs thecommunication device 190 to employ narrow beams for a UL soundingtransmission, an LBT procedure CDLBT prior to the UL soundingtransmission, a UL data transmission and an LBT procedure CDLBT prior tothe UL data. Namely, the beamwidth for the UL sounding transmission isassociated with that for the UL data transmission. Information aboutbeamwidth adjustment for the LBT procedure CDLBT may be transmitted bymeans of the UL grant related DCI 410 such as sound reference signal(SRS) for channel status information (CSI) measurement and Physicaldownlink share channel (PUSCH) scheduling. In some embodiments, thebeamwidth for the LBT procedure CDLBT is no less than the beamwidth forthe UL transmission ULT. In some embodiments, the beamwidth range (orbeam coverage) for the LBT procedure CDLBT includes the beamwidth range(or beam coverage) for the UL transmission ULT.

In some embodiments, the at least one parameter of the communicationdevice 190 (or the capability of the communication device 190) mayinclude a relation between its beamwidth and its beam direction. Thepointing direction of a particular beam which radiates the signal isdefined as the beam direction. A beamforming pointing direction (or beampeak direction) may be the geometric center of the half-power contour ofthe beam. Specifically, please refer to FIG. 7 and FIG. 8. FIG. 7 andFIG. 8 are schematic diagrams associated with the method 30 shown inFIG. 3. According to FIG. 7 and FIG. 8, the communication device 190 mayhave more than one panel for transmission or reception, and each panelmay have different antenna layouts which may cause different radiationpatterns. The antenna beam from a panel of a specific panel index issteered into a specific beam direction; namely, the beam direction (andthe beamwidth) is related to the panel index. In FIG. 7 and FIG. 8, thecommunication device 190 may report its panel indexes and itscorresponding (antenna) capability, which is beamwidth related, througha signal SS in Step 302. For example, panel index DX1 may correspond toa narrow beamwidth and a beam direction DN1, and panel index DX2 maycorrespond to a wide beamwidth and a beam direction DN2.

In FIG. 7, the communication device 190 may adjust the (energydetection) thresholds according to its capability and/or signaling fromthe base station BS in Step 304. Each of the (energy detection)thresholds corresponds to a panel index. Information about the (energydetection) thresholds corresponding to the panel indexes ofcommunication device 190 may be transmitted by means of the UL grantrelated DCI 410. The communication device 190 may perform the LBTprocedure CDLBT with wide beamwidth according to the (energy detection)threshold of lower energy level before the UL transmission ULT. When thecommunication device 190 performs the LBT procedure CDLBT with the panelindex DX2 corresponding to wide beamwidth, it may cover certain nodes450 within its beam coverage. Nevertheless, by decreasing the (energydetection) threshold during the LBT procedure CDLBT, the fairnessproblem is alleviated.

In FIG. 8, the communication device 190 may adjust the channel sensingtime (or the contention window sizes) according to its capability and/orLBT type indicated by the base station BS in Step 304. Each of thechannel sensing time corresponds to a panel index. Information about theLBT type may be transmitted by means of the UL grant related DCI 410.The LBT type in the UL grant related DCI 410 may be an N bit (forinstance, N=2) information, and may be, for instance, 00, 01, 10, or 11.The communication device 190 may determine the contention window sizeaccording to the LBT type and/or panel index. In some embodiments, thecontention window size may be configured by higher layer signals such asan RRC and/or MAC signal, and thus may not be indicated in the UL grantrelated DCI 410. Furthermore, the contention window sizes correspondingto different panel indexes but the same LBT type may be identical,similar, or different. The communication device 190 may perform the LBTprocedure CDLBT according to the panel index and/or LBT type indicatedby base station BS before UL transmission ULT. When the communicationdevice 190 performs the LBT procedure CDLBT with the panel index DX1corresponding to narrow beamwidth, it may filter certain nodes 450outside its beam coverage. The channel sensing time may remain shortwithout creating the fairness problem.

With the method 30, fairness problems, which occur when thecommunication device 190 performs a shorter LBT procedure (for instance,according to the indication from the base station BS) without taking itsbeamwidth (of each panel) into account, may be prevented.

FIG. 9 is a flowchart of a method 90 according to an example of thepresent invention. The method 90 may be utilized in a communicationdevice 190, for handling an LBT procedure in an unlicensed band. Themethod 90 includes the following steps:

Step 900: Start.

Step 902: Determining a first spatial domain filter for a first uplinktransmission.

Step 904: Determining a second spatial domain filter for a second uplinktransmission.

Step 906: End.

In current NR system, different channel(s) and/or signal(s) may betransmitted with different beam directions (for example, according todifferent QCL assumption and/or via different spatial domain filters).Besides, the communication device 190 may be served with a plurality oftransmission reception points (TRPs) so as to enhance spectrumefficiency. For example, the communication device 190 may transmitphysical uplink control channel (PUCCH) to a TRP and may dynamicallytransmit PUSCH to the TRP and/or another TRP according to UL CSI.Accordingly, before a UL transmission (for example, a first ULtransmission ULT1 or a second UL transmission ULT2 shown in FIG. 10)during the channel occupancy time, the communication device 190 mayreceive a beam indicator indicating a beam direction or a spatial domainfilter to perform the following UL transmission (that is, the first ULtransmission ULT1 or the second UL transmission ULT2) in the method 90.In some embodiments, the communication device 190 may receive a beamindicator indicating a beam direction or a spatial domain filter toperform a PUCCH transmission through RRC layer and/or MAC layersignal(s). In some embodiments, the communication device 190 may receiveabeam indicator indicating a beam direction or a spatial domain filterto perform a PUSCH transmission (for data transmission) through DCI. Insome embodiments, the communication device 190 may receive abeamindicator indicating a beam direction or a spatial domain filter toperform an (Aperiodic) SRS transmission (for UL CSI acquisition) throughRRC layer signal(s). In some embodiments, the first beam indicator orthe second beam indicator may be SRS resource indicator (SRI), spatialrelation information, spatial relation assumption, or spatial domaintransmission filter. In some embodiments, the first beam indicator orthe second beam indicator may be DCI. In some embodiments, the beamdirections or spatial domain filters may be determined by configurationof the base station BS from different layers such as RRC layer, MAClayer and/or Physical layer by DCI. Correspondingly, in someembodiments, the communication device 190 may determining a firstspatial domain filter for a first uplink transmission and determining asecond spatial domain filter for a second uplink transmission in Step902 or step 904.

Chances are that different UL transmissions for differentchannels/signals may be overlapped or spaced apart by a limited distance(for example, a time interval DST shown in FIG. 10) in time domain. Forexample, the time interval (or time distance) DST between the first ULtransmission ULT1 to be performed and the second UL transmission ULT2 tobe performed is less than a duration standard. However, it may berequired for the communication device 190 to perform an LBT procedure(for example, an LBT procedure CDLBT shown in FIG. 10) in an unlicensedband with limited number of beam direction(s) or spatial domainfilter(s) because of implementation limitation and/or power saving ofthe communication device 190. Particularly, in some embodiments, thecommunication device 190 is able to perform a UL transmission or an LBTprocedure in only one beam direction at a time. Namely, beam from thecommunication device 190 may only focus in one beam direction at a time,and the beam-formed transmission may only be done in one beam directionat a time. The communication device 190 may find out the infeasibilityof one LBT procedure for different UL transmissions of different ULchannels/signals with different beam directions according to the shorttime interval DST between the two channels/signals or the (partial)overlap between the two channels/signals. In some embodiments, theduration standard may be pre-determined (for instance, in thespecification) or configured by the base station BS. In someembodiments, the length of the duration standard may depend on the typeof UL channel(s)/signal(s). For example, the duration standard before aPUCCH transmission should be more than 16 microseconds for an LBTprocedure. The duration standard before a PUSCH transmission should bemore than 25 microseconds for an LBT procedure. In some embodiments, thecommunication device 190 may find out the length of the durationstandard by means of time interval information via RRC layer, MAC layer,and/or physical layer signals.

When the time interval DST between the first UL transmission ULT1 to beperformed and the second UL transmission ULT2 to be performed is lessthan a duration standard, the communication device 190 may perform beamalignment related procedure. In some embodiments, the communicationdevice 190 may determine a third spatial domain filter to perform an LBTprocedure CDLBT for both the first UL transmission ULT1 and the secondUL transmission ULT2 since the LBT procedure CDLBT can only be done inone beam direction at a time. In other words, the communication device190 may transmit a plurality of channel(s)/signal(s) with the same beamdirection (or spatial domain filter, QCL assumption) in the method 90.In some embodiments, the communication device 190 may determine a thirdspatial domain filter for transmitting at least one of first ULtransmission ULT1 or the second UL transmission ULT2. In someembodiments, at least one of first UL transmission ULT1 or the second ULtransmission ULT2 is transmitted by the third spatial domain filter.

The third spatial domain filter may be chosen from spatial domainfilters to perform the following UL transmissions according tosignificance or transmission timing of the following UL transmissions.FIG. 10 is a schematic diagram associated with the method 90 shown inFIG. 9. In FIG. 10, a dashed thick line with dots denotes approximateextent of the beam coverage of the communication device 190 for the LBTprocedure CDLBT, the first UL transmission ULT1, or the second ULtransmission ULT2. The transmission sequences before and after decisionof the third spatial domain filter in the time domain are illustrated atthe top and bottom of FIG. 10 respectively.

In FIG. 10, the first UL transmission ULT1 is indicated to be performedwith a first spatial domain filter DRN1 via a first beam indicator. Thesecond UL transmission ULT2 is indicated to be performed with a secondspatial domain filter DRN2 via a second beam indicator. In someembodiments, the communication device 190 selects a specific spatialdomain filter (that is, the first spatial domain filter DRN1) to performthe LBT procedure CDLBT, the first UL transmission ULT1 and the secondUL transmission ULT2 according to the priorities of configurationsignals for indicating beam direction, spatial domain filter, or QCLassumption in the method 90.

In some embodiments, the communication device 190 selects a specificspatial domain filter (that is, a first spatial domain filter DRN1) toperform the LBT procedure CDLBT, the first UL transmission ULT1 and thesecond UL transmission ULT2 according to channel/signal types in themethod 90. In this case, channel/signal type of the first ULtransmission ULT1 may affect its priority; channel/signal type of thesecond UL transmission ULT2 may affect its priority. For example, aPUCCH transmission has priority over a PUSCH transmission scheduled withspatial domain filter indicated by physical layer, and hence thecommunication device 190 selects the spatial domain filter fortransmitting the PUCCH signal to perform the LBT procedure CDLBT, thePUCCH transmission and the PUCCH transmission. In some embodiments, apriority order among transmission may be: MAC layer may qualify for thefirst priority; the second priority may reside in RRC layer; physicallayer may be accorded a third priority; the fourth priority is given toa transmission scheduled without beam indicator. In some embodiments, apriority order among transmission may be: PUCCH transmission may qualifyfor the first priority; the second priority may reside in Aperiodic SRStransmission; PUSCH transmission scheduled with spatial domain filterindicated by physical layer may be accorded a third priority; the fourthpriority is given to PUSCH transmission scheduled without beamindicator.

In some embodiments, the communication device 190 selects a specificspatial domain filter (that is, the first spatial domain filter DRN1) toperform the LBT procedure CDLBT, the first UL transmission ULT1 and thesecond UL transmission ULT2 according to UL signal/information contentsin the method 90. In this case, signal/information content of the firstUL transmission ULT1 may affect its priority; signal/information contentof the second UL transmission ULT2 may affect its priority. For example,a PUCCH transmission including hybrid automatic repeat request (HARQ)has priority over a PUCCH transmission including scheduling request, andhence the communication device 190 selects the spatial domain filter forPUCCH transmission including HARQ to perform the LBT procedure CDLBT,the former PUCCH transmission and the latter PUCCH transmission. In someembodiments, a priority order among transmission may be: HARQ (forinstance, PUCCH including HARQ for DL assignment) may qualify for thefirst priority; the second priority may reside in scheduling request;CSI (for instance, PUSCH including CSI) may be accorded a thirdpriority; the fourth priority is given to channel(s)/signal(s) withoutuplink control information (UCI).

As set forth above, in some embodiments, the third spatial domain filteris associated with either the first spatial domain filter DRN1 or thesecond spatial domain filter. In some embodiments, the third spatialdomain filter is either the first spatial domain filter DRN1 or thesecond spatial domain filter DRN2. In some embodiments, the thirdspatial domain filter is determined according to a priority rule betweenthe first uplink transmission and the second uplink transmission. Insome embodiments, the third spatial domain filter is (or equals) thefirst spatial domain filter DRN1 when the priority of the first ULtransmission ULT1 is higher than the priority of the second ULtransmission ULT2. In some embodiments, the third spatial domain filteris (or equals) the second spatial domain filter DRN2 belonging to thesecond UL transmission ULT2 with higher priority than the priority ofthe first UL transmission ULT1. In the method 90, the first ULtransmission ULT1 and the second UL transmission ULT2 are performedaccording to the third direction.

In some embodiments, the communication device 190 may transmit aplurality of channel(s)/signal(s) with the same beam direction, spatialdomain filter, or QCL assumption according to the transmission timing(for example, according to the first UL channel(s)/signal(s) intent ontransmission). In some embodiments, the third spatial domain filter isdetermined according to a chronological order between the first uplinktransmission and the second uplink transmission. In some embodiments,the third spatial domain filter is (or equals) the first spatial domainfilter DRN1 when the first UL transmission ULT1 is scheduled prior tothe second UL transmission ULT2 as shown in FIG. 10. In someembodiments, the third spatial domain filter is (or equals) the secondspatial domain filter DRN2 when the second UL transmission ULT2 isscheduled prior to the first UL transmission ULT1.

The third spatial domain filter may differ from spatial domain filtersto perform the following UL transmissions, but may be associated withthe spatial domain filters to perform the following UL transmissions.FIG. 11 and FIG. 12 are schematic diagrams associated with the method 90shown in FIG. 9. In FIG. 11 and FIG. 12, the first UL transmission ULT1is indicated to be performed with a first spatial domain filter DRN1 viaa first beam indicator. The second UL transmission ULT2 is indicated tobe performed with a second spatial domain filter DRN2 via a second beamindicator. The communication device 190 selects a specific spatialdomain filter (that is, a third spatial domain filter DRN3) to performthe LBT procedure CDLBT and the following UL transmissions in the method90.

In some embodiments, the third spatial domain filter DRN3 differs fromeither the first spatial domain filter DRN1 or the second spatial domainfilter DRN2; however, the third spatial domain filter DRN3 is associatedwith the first spatial domain filter DRN1 and the second spatial domainfilter DRN2. In some embodiments, the base station BS transmits asynchronization signal block (SSB) signal with width beamwidth, a firstDL reference signal (RS) with narrow width beamwidth, and a second DL RSwith narrow width beamwidth. There is a relation between the SSB signal,the first DL RS, and the second DL RS. For example, in some embodiments,the QCL assumption of the first DL RS and the second DL RS indicate thesame RS (for example, the SSB signal). In some embodiments, the SSBsignal is associated with the first DL RS according to the QCLassumption. If the communication device 190 is able to receive the SSBsignal, for example, with third spatial domain filter DRN3, thecommunication device 190 is able to receive the first DL RS, forexample, with the first spatial domain filter DRN1. Similarly, the SSBsignal is also associated with the second DL RS according to the QCLassumption. If the communication device 190 is able to receive the SSBsignal with third spatial domain filter DRN3, the communication device190 is able to receive the second DL RS, for example, with the secondspatial domain filter DRN2.

In such a situation, the communication device 190 may determine spatialdomain receiving filter for the LBT procedure CDLBT according to aspatial domain receiving filter for receiving the SSB signal. Then, thecommunication device 190 may perform the LBT procedure CDLBT by usingthe same spatial domain receiving filter for receiving the SSB signal.The first DL RS may correspond to the first UL transmission ULT1, andthe second DL RS may correspond to the second UL transmission ULT2. Thecommunication device 190 may perform the LBT procedure CDLBT with athird beam coverage corresponding to the SSB signal. The third beamcoverage corresponding to the third spatial domain filter DRN3 covers afirst beam coverage of the first UL transmission ULT1 corresponding tothe first spatial domain filter DRN1 or/and a second beam coverage ofthe second UL transmission ULT2 corresponding to the second spatialdomain filter DRN2. The third spatial domain filter DRN3 correspondingto the SSB signal may be derived according to the first spatial domainfilter DRN1 corresponding to the first DL RS and the second spatialdomain filter DRN2 corresponding to the first DL RS. In the method 90,the LBT procedure CDLBT for both the first UL transmission ULT1 and thesecond UL transmission ULT2 is performed with the third spatial domainfilter DRN3. In some embodiments, the third spatial domain filter isdetermining according to a reference signal. The reference signal is atarget reference signal for determining the first spatial domain filterDRN1 corresponding to the first UL transmission ULT1 corresponding toand the second spatial domain filter DRN2 corresponding to the seconduplink transmission ULT2.

In FIG. 11, the first UL transmission ULT1 and the second ULtransmission ULT2 are performed according to different spatial domainfilters in the method 90. Specifically, the first UL transmission ULT1is performed according to the first spatial domain filter DRN1; thesecond UL transmission ULT2 is performed according to the second spatialdomain filter DRN2.

In FIG. 12, both the first UL transmission ULT1 and the second ULtransmission ULT2 are performed according to the same spatial domainfilter in the method 90. In some embodiments, the first spatial domainfilter DRN1, the second spatial domain filter DRN2, and the thirdspatial domain filter DRN3 are the same. In some embodiments, the firstspatial domain filter DRN1, the second spatial domain filter DRN2, andthe third spatial domain filter DRN3 are determined according to atarget reference signal In the method 90, the first UL transmission ULT1and the second UL transmission ULT2 are performed according to the thirdspatial domain filter DRN3. The communication device 190 may determinespatial domain receiving filter for UL transmission(s) according to aspatial domain receiving filter for receiving the SSB signal. Then, thecommunication device 190 may perform UL transmission(s) by using thesame spatial domain receiving filter for receiving the SSB signal.

With the method 90, spatial domain filter for a (directional) LBTprocedure CDLBT may be determined even under different QCL assumptionsfor the following UL transmissions.

FIG. 13 is a flowchart of a method 13 according to an example of thepresent invention. The method 13 may be utilized in a communicationdevice 190, for handling an LBT procedure in an unlicensed band. Themethod 13 includes the following steps:

Step 1300: Start.

Step 1302: Determining a first spatial domain filter for a first uplinktransmission.

Step 1304: Determining a second spatial domain filter for a seconduplink transmission.

Step 1306: Transmitting at least one of the first uplink transmissionand the second uplink transmission by a third spatial domain filter.

Step 1308: Puncturing, dropping or postponing one of the first ULtransmission and the second UL transmission.

Step 1310: End.

Certain steps in the method 13 duplicate certain steps in the method 90.For instance, Step 1302 and Step 1304 are similar to Step 902 and Step904 respectively, and hence are not detailed redundantly. In someembodiments of the method 90, the communication device 190 performs afirst LBT procedure (for example, a first LBT procedure CDLBT1 shown inFIG. 14) in an unlicensed band for one of the first UL transmission ULT1and the second UL transmission ULT2 with the same beam direction orspatial domain filter to perform the following UL transmission. Supposethe first LBT procedure CDLBT1 comes before the first UL transmissionULT1 and the second UL transmission ULT2 during the channel occupancytime in time or order. The beam direction or spatial domain filter toperform the first LBT procedure CDLBT1 is identical to the beamdirection or spatial domain filter to perform the subsequent ULtransmission (the first UL transmission ULT1 or the second ULtransmission ULT2). Chances are that the first UL transmission ULT1 tobe performed and the second UL transmission ULT2 to be performed may beoverlapped or spaced apart by a limited time interval (for example, atime interval DST shown in FIG. 14). However, beam from thecommunication device 190 may only focus in one beam direction at a time.The communication device 190 may find out the infeasibility of the firstLBT procedure CDLBT1 adopted for both the first UL transmission ULT1with the first spatial domain filter DRN1 and the second UL transmissionULT2 with the second spatial domain filter DRN2 according to the shorttime interval DST therebetween or the (partial) overlap therebetween. Insuch a situation, the communication device 190 transmitting at least oneof the first UL transmission ULT1 and the second UL transmission ULT2 bya third spatial domain filter in Step 1306. In Step 1308, one of thefirst UL transmission and the second UL transmission is punctured ordropped.

To determine beam direction or spatial domain filter for the(directional) first LBT procedure CDLBT1, please refer to FIG. 14. FIG.14 is a schematic diagram associated with the method 13 shown in FIG.13. In FIG. 14, a dashed thick line with dots denotes approximate extentof the beam coverage of the communication device 190 for the first LBTprocedure CDLBT1, a second LBT procedure CDLBT2, the first ULtransmission ULT1, or the second UL transmission ULT2. The transmissionsequences before and after the adoption of the method 13 in the timedomain are illustrated at the top and bottom of FIG. 14 respectively.

In FIG. 14, the first UL transmission ULT1 is performed before thesecond UL transmission ULT2, while the second UL transmission ULT2 takespriority over the first UL transmission ULT1. In such a situation, thecommunication device 190 performs the first LBT procedure CDLBT1 for thefirst UL transmission ULT1 with a first spatial domain filter DRN1 inStep 1306. Furthermore, a portion of the first UL transmission ULT1 withlower priority may be punctured in Step 1308. In this manner, thecommunication device 190 is able perform the second LBT procedure CDLBT2in an unlicensed band for the second UL transmission ULT2 (which isranked as a higher priority) with the second spatial domain filter DRN2different from the first spatial domain filter DRN1 for the first ULtransmission ULT1, which is ranked as a lower priority. By means of thepuncturing, there may be enough time for the second LBT procedure CDLBT2because there are no prior UL transmissions before the head (front)portion of the second UL transmission ULT2. In other words, the first ULtransmission ULT1 is punctured when the priority of the second ULtransmission ULT2 is higher than the priority of the first ULtransmission ULT1.

In some embodiments, the UL transmission with lower priority (that is,the first UL transmission ULT1) is tail-punctured. In other words, thetail (back) portion of the UL transmission with lower priority ispunctured. In some embodiments, an insignificant portion of the ULtransmission with lower priority (that is, the first UL transmissionULT1) is punctured. The insignificant portion may be head (front)portion, tail portion, or discrete portion. In some embodiments, thepuncturing involves recoding.

To determine beam direction or spatial domain filter for the(directional) first LBT procedure CDLBT1, please refer to FIG. 15. FIG.15 is a schematic diagram associated with the method 13 shown in FIG.13. In FIG. 15, the first UL transmission ULT1 is performed before thesecond UL transmission ULT2, while the second UL transmission ULT2 takespriority over the first UL transmission ULT1. In such a situation, thecommunication device 190 performs the first LBT procedure CDLBT1 for ULchannel/signal with higher priority (that is, the second UL transmissionULT2) with a second spatial domain filter DRN2 in Step 1306.Furthermore, UL channel/signal with lower priority (that is, the firstUL transmission ULT1) may be dropped in Step 1308. By means of thedropping, there may be enough time for the communication device 190 toperform the first LBT procedure CDLBT1 for the second UL transmissionULT2 with higher priority, because there are no prior UL transmissionsbefore the head (front) portion of the second UL transmission ULT2. Inother words, the first UL transmission ULT1 is dropped, when thepriority of the second UL transmission ULT2 is higher than the priorityof the first UL transmission ULT1.

In some embodiments, the first UL transmission ULT1 is dropped in Step1308 especially when the length of the first UL transmission ULT1 isless than a length standard. The length standard may be configured bythe base station BS or may be a predetermined value.

To determine beam direction or spatial domain filter for the(directional) first LBT procedure CDLBT1, please refer to FIG. 16. FIG.16 is a schematic diagram associated with the method 13 shown in FIG.13. In FIG. 16, the first UL transmission ULT1 is performed before thesecond UL transmission ULT2, and the first UL transmission ULT1 takespriority over the second UL transmission ULT2. In such a situation, thecommunication device 190 performs the first LBT procedure CDLBT1 for thefirst UL transmission ULT1 with a first spatial domain filter DRN1 inStep 1306. Furthermore, the latter UL channel/signal (that is, second ULtransmission ULT2) ranked as a lower priority may be postponed and thelatter part of the second UL transmission ULT2 may be punctured in Step1308. In other words, the UL transmission (that is, the second ULtransmission ULT2) with lower priority may be postponed (especially whenthe second UL transmission ULT2 comes after the first UL transmissionULT1). Besides, a portion of the UL transmission (that is, the second ULtransmission ULT2) with lower priority may be punctured (especially whenthe second UL transmission ULT2 comes after the first UL transmissionULT1).

In this manner, the communication device 190 is able perform a secondLBT procedure CDLBT2 for the second UL transmission ULT2 (which isranked as a lower priority) with the second spatial domain filter DRN2different from the first spatial domain filter DRN1 for the first ULtransmission ULT1, which is ranked as a higher priority. By means of thepuncturing, there may be enough time for the second LBT procedure CDLBT2because there are no prior UL transmissions before the head (front)portion of the second UL transmission ULT2. In other words, the secondUL transmission ULT2 is punctured when the priority of the first ULtransmission ULT1 is higher than the priority of the second ULtransmission ULT2.

In some embodiments, the UL transmission with lower priority (that is,second UL transmission ULT2) is tail-punctured. In other words, the tail(back) portion of the UL transmission with lower priority is punctured.In some embodiments, an insignificant portion of the UL transmissionwith lower priority (that is, second UL transmission ULT2) is punctured.The insignificant portion may be head (front) portion, tail portion, ordiscrete portion. In some embodiments, the puncturing involves recoding.

To determine beam direction or spatial domain filter for the(directional) first LBT procedure CDLBT1, please refer to FIG. 17. FIG.17 is a schematic diagram associated with the method 13 shown in FIG.13. In some embodiments, the first UL transmission ULT1 is performedbefore the second UL transmission ULT2, and the first UL transmissionULT1 takes priority over the second UL transmission ULT2. In such asituation, the communication device 190 performs the first LBT procedureCDLBT1 for UL channel/signal with higher priority (that is, the first ULtransmission ULT1) with a first spatial domain filter DRN1 in Step 1306.Furthermore, UL channel/signal with lower priority (that is, the secondUL transmission ULT2) may be dropped in Step 1308. In other words, thesecond UL transmission ULT2 is dropped when the priority of the first ULtransmission ULT1 is higher than the priority of the second ULtransmission ULT2. In some embodiments, the second UL transmission ULT2is dropped in Step 1308 especially when the length of the second ULtransmission ULT2 is less than a length standard. The length standardmay be configured by the base station BS or may be a predeterminedvalue.

With the method 13, beam direction or spatial domain filter for a(directional) first LBT procedure CDLBT1 maybe determined even underdifferent QCL assumptions for the following UL transmissions.

FIG. 18 is a flowchart of a method 18 according to an example of thepresent invention. The method 18 may be utilized in a base station BS,for handling an LBT procedure in an unlicensed band. The method 18includes the following steps:

Step 1800: Start.

Step 1802: Scheduling UL resource to ensure a distance between a firstUL transmission to be performed by a communication device 190 and asecond UL transmission to be performed by the communication device 190is larger than a tolerance standard for an LBT procedure correspondingto either the first UL transmission or the second UL transmission on afirst carrier.

Step 1804: End.

Suppose the first UL transmission is performed before the second ULtransmission during the channel occupancy time. The communication device190 may not expect that the first UL transmission and the second ULtransmission have different QCL assumption. To solve problems resultedfrom different QCL assumptions, the base station BS may schedule ULresource so that a distance (such as a time interval and/or a timedistance) between a first UL transmission to be performed by thecommunication device 190 and a second UL transmission to be performed bythe communication device 190 is longer than a tolerance standard (suchas a duration standard). In this manner, there would be enough time fora second LBT procedure in an unlicensed band corresponding to the secondUL transmission. More specifically, after the first UL transmission isperformed by the communication device 190, the time interval ofmicroseconds comes to serve as a gap. The time interval will give thecommunication device 190 time to perform the second LBT procedure forthe second UL transmission. Since the second LBT procedure correspondingto the second UL transmission is performed by the communication device190 during the time interval, the time interval should be no less thanthe tolerance standard, which may be predetermined in astandard/specification, configured by the base station BS or fixed. Insome embodiments, the tolerance standard is associated with prioritiesof the first UL transmission and the second UL transmission. In someembodiments, the length of the duration standard may depend on types ofUL channel(s)/signal(s), for example, the channel/signal type of thefirst UL transmission or the second UL transmission.

Similarly, to solve problems resulted from different QCL assumptions,the base station BS may schedule UL resource so that a distance (such asa frequency difference and/or a frequency distance) between a first ULtransmission to be performed by the communication device 190 and asecond UL transmission to be performed by the communication device 190is larger than a tolerance standard (such as a difference standard). Insome embodiments, a frequency band for the first UL transmission maydiffer from a frequency band for the second UL transmission. In someembodiments, the first UL transmission and the second UL transmissionmay be in the same band or component carrier (CC) or within a frequencyrange. The frequency difference should be no less than the tolerancestandard, which may be predetermined in a standard/specificationconfigured by the base station BS, or fixed. In some embodiments, thetolerance standard is associated with priorities of the first ULtransmission and the second UL transmission. In some embodiments, themagnitude of the tolerance standard may depend on types of ULchannel(s)/signal(s), for example, the channel/signal type of the firstUL transmission or the second UL transmission.

With the method 18, there is no need to solve fairness problems, whichoccur when the communication device 190 performs a shorter LBT procedurewithout taking its beamwidth (of each panel) into account. In addition,it is not necessary for the communication device 190 to determine beamdirection or spatial domain filter for a (directional) LBT procedureunder different QCL assumptions for the following UL transmissions.

In summary, the present invention adjusts at least one parameter of thecommunication device to solve fairness problems. The present inventiondetermines a third spatial domain filter to perform an LBT procedure forboth the first UL transmission and the second UL transmission accordingto a sophisticated algorithm even under different QCL assumptions forthe following UL transmissions.

Alternatively, the present invention punctures or drops certain ULtransmission to ensure an LBT procedure according to anothersophisticated algorithm under different QCL assumptions for thefollowing UL transmissions. A base station of the present invention mayschedule UL resource to avoid fairness problems or problems resultedfrom different QCL assumptions.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A device for handling channel access procedure,comprising: a storage device, for storing instructions of: receiving anindication for an uplink transmission; determining at least oneparameter of the device for a listen-before-talk procedure according toa capability of the device or a signaling from a base station; andperforming the uplink transmission according to the indication; and aprocessing circuit, coupled to the storage device, configured to executethe instructions stored in the storage device.
 2. The device of claim 1,wherein the signaling from the base station is comprised in theindication.
 3. The device of claim 1, wherein the instructions furthercomprises reporting the capability of the device.
 4. The device of claim1, wherein the capability of the device comprises beamwidth of thedevice.
 5. The device of claim 4, wherein the beamwidth of the device iswide beamwidth, narrow beamwidth, or variable beamwidth.
 6. The deviceof claim 1, wherein the at least one parameter of the device comprises athreshold for energy detection during the listen-before-talk procedure.7. The device of claim 1, wherein the at least one parameter of thedevice comprises a channel sensing time for the listen-before-talkprocedure.
 8. The device of claim 1, wherein the at least one parameterof the device comprises beamwidth of the device.
 9. A device forhandling channel access procedure, comprising: a storage device, forstoring instructions of: determining a first spatial domain filter for afirst uplink transmission; and determining a second spatial domainfilter for a second uplink transmission; and a processing circuit,coupled to the storage device, configured to execute the instructionsstored in the storage device.
 10. The device of claim 9, wherein a timeinterval between the first uplink transmission to be performed and thesecond uplink transmission to be performed is less than a durationstandard.
 11. The device of claim 10, wherein the time interval ispredetermined or configured by a network.
 12. The device of claim 9,wherein the instructions further comprises: determining a third spatialdomain filter for transmitting at least one of the first uplinktransmission or the second uplink transmission.
 13. The device of claim12, wherein the instructions further comprises: transmitting at leastone of the first uplink transmission or the second uplink transmissionby the third spatial domain filter.
 14. The device of claim 12, whereina third spatial domain filter is either the first spatial domain filteror the second spatial domain filter.
 15. The device of claim 9, whereinthe instructions further comprises: performing a listen-before-talkprocedure before transmitting at least one of the first uplinktransmission or the second uplink transmission.
 16. The device of claim9, wherein the instructions further comprises: determining a thirdspatial domain filter according to a priority rule between the firstuplink transmission and the second uplink transmission.
 17. The deviceof claim 16, wherein the third spatial domain filter equals the firstspatial domain filter when a priority of the first uplink transmissionis higher than a priority of the second uplink transmission, wherein thethird spatial domain filter equals the second spatial domain filter whenthe priority of the second uplink transmission is higher than thepriority of the first uplink transmission.
 18. The device of claim 9,wherein the instructions further comprises determining a third spatialdomain filter according to a chronological order between the firstuplink transmission and the second uplink transmission.
 19. The deviceof claim 18, wherein the third spatial domain filter equals the firstspatial domain filter when the first uplink transmission is scheduledprior to the second uplink transmission, wherein the third spatialdomain filter equals the second spatial domain filter when the seconduplink transmission is scheduled prior to the first uplink transmission.20. The device of claim 9, wherein a third spatial domain filter isdetermining according to a reference signal.
 21. The device of claim 20,wherein the reference signal is a target reference signal fordetermining the first spatial domain filter of the first transmissionand the second spatial domain filter of the second uplink transmission.22. The device of claim 9, wherein the instructions further comprises:transmitting at least one of the first uplink transmission and thesecond uplink transmission by a third spatial domain filter; andpuncturing, dropping or postponing one of the first uplink transmissionand the second uplink transmission.
 23. The device of claim 22, whereinthe second uplink transmission is dropped or punctured when a priorityof the first uplink transmission is higher than a priority of the seconduplink transmission, wherein the first uplink transmission is dropped orpunctured when the priority of the second uplink transmission is higherthan the priority of the first uplink transmission.
 24. The device ofclaim 22, wherein one of the first uplink transmission and the seconduplink transmission is postponed when coming after another one of thefirst uplink transmission and the second uplink transmission.
 25. Thedevice of claim 9, wherein the instructions further comprises:transmitting the first uplink transmission and the second uplinktransmission by a third spatial domain filter, wherein the first spatialdomain filter, the second spatial domain filter, and the third spatialdomain filter are determined according to a target reference signal. 26.A method for handling channel access procedure, comprising: receiving anindication for an uplink transmission; determining at least oneparameter of the device for a listen-before-talk procedure according toa capability of the device or a signaling from a base station; andperforming the uplink transmission according to the indication.
 27. Themethod of claim 26, wherein the signaling from the base station iscomprised in the indication.
 28. The method of claim 26, wherein theinstructions further comprises reporting the capability of the device.29. The method of claim 26, wherein the capability of the devicecomprises beamwidth of the device.
 30. The method of claim 29, whereinthe beamwidth of the device is wide beamwidth, narrow beamwidth, orvariable beamwidth.
 31. The method of claim 26, wherein the at least oneparameter of the device comprises a threshold for energy detectionduring the listen-before-talk procedure.
 32. The method of claim 26,wherein the at least one parameter of the device comprises a channelsensing time for the listen-before-talk procedure.
 33. The method ofclaim 26, wherein the at least one parameter of the device comprisesbeamwidth of the device.
 34. A method for handling channel accessprocedure, comprising: determining a first spatial domain filter for afirst uplink transmission; and determining a second spatial domainfilter for a second uplink transmission.
 35. The method for claim 34,wherein a time interval between the first uplink transmission to beperformed and the second uplink transmission to be performed is lessthan a duration standard.
 36. The method of claim 35, wherein the timeinterval is predetermined or configured by a network.
 37. The method forclaim 34, further comprising: determining a third spatial domain filterfor transmitting at least one of the first uplink transmission or thesecond uplink transmission.
 38. The method for claim 37, furthercomprising: transmitting at least one of the first uplink transmissionor the second uplink transmission by the third spatial domain filter.39. The method of claim 37, wherein a third spatial domain filter iseither the first spatial domain filter or the second spatial domainfilter.
 40. The method for claim 34, further comprising: performing alisten-before-talk procedure before transmitting at least one of thefirst uplink transmission or the second uplink transmission.
 41. Themethod for claim 34, further comprising: determining a third spatialdomain filter according to a priority rule between the first uplinktransmission and the second uplink transmission.
 42. The method of claim41, wherein the third spatial domain filter equals the first spatialdomain filter when a priority of the first uplink transmission is higherthan a priority of the second uplink transmission, wherein the thirdspatial domain filter equals the second spatial domain filter when thepriority of the second uplink transmission is higher than the priorityof the first uplink transmission.
 43. The method for claim 34, furthercomprising: determining a third spatial domain filter according to achronological order between the first uplink transmission and the seconduplink transmission.
 44. The method of claim 43, wherein the thirdspatial domain filter equals the first spatial domain filter when thefirst uplink transmission is scheduled prior to the second uplinktransmission, wherein the third spatial domain filter equals the secondspatial domain filter when the second uplink transmission is scheduledprior to the first uplink transmission.
 45. The method of claim 34,wherein a third spatial domain filter is determining according to areference signal.
 46. The method of claim 45, wherein the referencesignal is a target reference signal for determining the first spatialdomain filter of the first transmission and the second spatial domainfilter of the second uplink transmission.
 47. The method for claim 34,further comprising: transmitting at least one of the first uplinktransmission and the second uplink transmission by a third spatialdomain filter; and puncturing, dropping or postponing one of the firstuplink transmission and the second uplink transmission.
 48. The methodof claim 47, wherein the second uplink transmission is dropped orpunctured when a priority of the first uplink transmission is higherthan a priority of the second uplink transmission, wherein the firstuplink transmission is dropped or punctured when the priority of thesecond uplink transmission is higher than the priority of the firstuplink transmission.
 49. The method of claim 47, wherein one of thefirst uplink transmission and the second uplink transmission ispostponed when coming after another one of the first uplink transmissionand the second uplink transmission.
 50. The method for claim 34, furthercomprising: transmitting the first uplink transmission and the seconduplink transmission by a third spatial domain filter, wherein the firstspatial domain filter, the second spatial domain filter, and the thirdspatial domain filter are determined according to a target referencesignal.